Running Out Of Room!

How the hell do you guys hold everything?
I'm new to 90 BLU, and I've been working on gear sets.
A lot of my gear is shared between spells, but I'm about 5 slots away from not being able to hold all my BLU gear at once.
I've got a tanking set which is mostly Def atm. A haste set for those spells that nothing else matters but recast. STR/DEX Set, STR/VIT set, INT/VIT set, INT/MND set, MND set (Mostly for magic hammer when I'm not in abyssea), and a TP build (Which I doubt has much effect when I'm constantly casting). I'm a little stumped on whether I should use AF body and relic head for Blue Magic Skill on some sets over whatever their mod is. But I guess that's something I'll just have to figure out. But how I am supposed to hold 20-30 more things (MDT, PDT, eva sets, and additions to the sets I've listed,) I don't have a damn clue.

I have to keep generally normally unused gear on mnk that I have (hybrid sets, eva gear, some weapons) in my satchel so if I happen to need them I can use them. I'm usually about 70/80 just with stuff I use on mnk. Could satchel some meds and tools, but that would get annoying.

Prioritize what you need, satchel the rest.

I don't have satchel or any money haha.
Basically in my sack I hold all my usable items (IE: Meds, Foods, Stables Collars, Warp Cudgel.) And the rest of the space usually goes to me swapping out random drops from my limited inventory space. But usually leaving with nothing but my gear and usable items, between both my inventory and sack I've only got about 10-15 free slots for drops.